The late Edo period has witnessed frequent outbreaks of epidemic disease. The average people，unable to access reliable medical care，could only save themselves by turning to superstition. Meanwhile，Japanese Confucianism and Kampo medicine underwent important changes；positivism began to gain attention. In that context，Rangaku rose from the absorption of modern Western medicine. By studying the human body，Rangaku scholars were convinced of the idea “everyone is human”. As their understanding of the world broadened and deepened，they pursued the universal truth，broke the traditional Chinese-foreign system and advocate the equal conception of nation，and tried to conceive a social institution to bring down the Tokugawa feudal hierarchy. In this way，Japan took its first step to modernization.